In the study, conducted at Duke University and Arkansas Children's Hospital, 33 children with peanut allergies were given carefully measured, incremental doses of peanuts. The initial doses were as tiny as one-1000th of a peanut and were administered in powder or liquid form.

Over several months, the children were given increasing doses, until they were consuming up to 15 peanuts per day without an allergic reaction. The most important finding was that half of the children who completed two and a half years of the therapy -- five children -- are now allergy-free.

"They're eating peanut butter and jelly sandwiches," said Dr. Wesley Burks, chief of the Division of Pediatric Allergy and Immunology at Duke. "They're not having allergic reactions and we really anticipate [the immunity] will last for the rest of their lives."

Most of the other study participants continue to receive daily maintenance doses of peanuts.

Burks said that results from this study could aid in developing treatment for many types of food allergies, "in the next few years."

With 3.3. million Americans suffering from nut allergies, that is reason to be hopeful. Children and adults with severe peanut allergies have been known to go into anaphylaxis or even die from exposure to even a minute amount of peanuts or other nuts.

Burks cautioned strongly that parents and other doctors not part of a study should not try the experiment on their own. It can have fatal consequences.

Similar studies that aim to desensitize children to certain allergens have been done in the past and the notion of building tolerance through exposure has been floated in the medical community for a century.

Some say such studies may also provide evidence that increasingly popular total nut bans in places such as schools and airplanes may actually be doing more harm than good.

"What we do with nut bans is actually make the problem worse," Harvard medical sociology professor Dr. Nicholas Christakis said. "We increase anxiety, we decrease exposure to nuts, which might increase the actual epidemic that we're trying to fight."

This study doesn't prove that theory, but Gina Clowes, who founded allergymoms.com, said she's "over-the-moon" about the increasing number of studies that may one day lead to treatment for her son Daniel and the millions like him.